Textile winding machines



y 8, 1962 JQONEYILL FISHER. ETAL 3,033,477

TEXTILE WINDING MACHINES Filed Sept. 11, 1959 Inventorsdi f PREV OWE/[LF/Sf/[fi M W omey States nite 1 3,033,477 TEXTELE WINDING MACHINESJeffrey ONeili Fisher, Dainebury, Golder-oft Common,

Caerleon, and Eric Wilson, Stevenage, England, assignors to BritishNylon Spinners Limited, Pontypool,

England Filed Sept. 11, 1959, Ser. No. 839,362 2 Claims. (Cl. 242-263)fined as including downtwisters, doublers, and similar machines whereinthe yarn proceeds in a downward direction to the spindle where it iswound up, such as the drawtwisting apparatus claimed in British patentspecification No. 543,466, which is designed for drawing syntheticlinear polymers e.g. polyamides.

After yarn consisting of such a synthetic linear polymer, for instance,polyhexamethylene adipamide, has been wound on to a bobbin or tube so asto form a package and is allowed to remain for a time on the saidpackage, in accordance with the requirements of textile usage, the yarngradually tends to contract somewhat. This tendency to contract has theeffect of producing an increased tension or strain in the yarn. In thecase of a tapered package this change is not uniform, but is found to beaccentuated in those parts of the yarn which occupy the tapered portionor portions of the package, supposedly because the yarn in these regionstends to have less resilient yarn beneath it to act as a cushion andpermit contraction, than the yarn elsewhere. Be this as it may, however,and the invention is in no way dependent on the correctness of thetheory outlined above, the fact remains that when such yarn is removedfrom the tapered package and woven into a fabric, undesirable light anddark bars or stripes are often observable in the weft. These stripes arevisible both before and after dyeing and are known as the barr effect.

Now the lower the lay ratio employed in winding, the closer together arethe above-mentioned stripes. Moreover, by bringing the stripes closeenough together, it has been shown experimentally that they can thus bemasked or made unnoticeable so that they no longer detract from theappearance of the woven fabric.

The lay ratio, sometimes defined as the number of coils of yarn per inchof package measured along the axis of the bobbin, is proportional to thethroughput of yarn divided by the traverse frequency. For a given degreeof inserted twist, the lay ratio becomes proportional to the speed ofthe bobbin spindle divided by the traverse frequency. The lay ratio canbe reduced therefore by decreasing the bobbin speed and/ or increasingthe traverse frequency. But it would be economically undesirable todecrease the bobbin speed because this is tantamount to reducing thethroughput, i.e. lowering the output. A remedy for barr was accordinglysought in an increased traverse frequency. Modern winding machinerydesigned for synthetic yarn is however accurately made and capable of ahigh speed of running, for instance, a spindle speed of 7,500revolutions per minute corresponding, for a certain degree of twist, toa throughput of 1,500 feet per minute. In order therefore to achieve asufiiciently low lay ratio to mask the barr atent eifcct, relativelyhigh traverse speeds are required, namely, of the order of 50-1-00cycles per minute. Such traverse speeds have not hitherto beenpractically attainable but it has now been found that winding at thisrange of speed can be accomplished by means of the following machine,the subject of the present invention. In this way it is accordinglypossible to wind yarn consisting of synthetic linear polymers, e.g. apolyamide such as polyhexamethyL ene adipa-mide, without the fault ofbarr being noticeable in fabric woven from the said yarn.

The following table illustrates the relationship between old rayonwinding machines (A), modern Winding machines for synthetic yarn (B) andthe present winding machines (C). The figures quoted are necessarilyvery inexact because naturally the speeds employed vary so considerably.It is however clear that the speed of the traverse of the presentmachines has not been practically obtainable before. The lay ratio hasbeen calculated in the following way:

- Definition of lay ratio; number of coils per inch of package.

Circumference of package; assumed to be 3".

Length of stroke of traverse (i.e. half cycle); assumed to be 4". i

The lay ratio is then given by the expression,

Throughput in feet per minute) E X 1 Cycles of traverse per minute 3 4X2Spindle, Through- Cycles Feet per Lay Machine r.p.m. put feet per cycleratio per min. Minute The invention relates to textile winding machines,which comprise in combination a spindle adapted to Wind yarn packages, atraverse mechanism therefor, a rotary motor with crank to convey, bymeans of conventional connecting means, a reciprocatory motion,corresponding approximately to a simple harmonic motion, to saidtraverse mechanism, the rotary motor itself being movably mounted so asto be capable of reciprocating in the direction of the aforesaidreciprocatory motion, a servomechanism for causing the said rotary motorto reciprocate in accordance with the contour of a cam, the follower ofwhich actuates the servomechanism, so that the reciprocatory motion dueto therotary motor is super-' posed on the reciprocatory motion due tothe cam, the contour of which latter is designed so that the traversemechanism produces a double taper yarn package.

The present machines enjoy the advantages of a simple and robustconstruction. Since the motion of the traverse isnearly simple harmonic,or, in other words, since the time/ displacement curve representsapproximate: 1y a sine wave, the absence of shock to the mechanism isensured. Y

The rotary motor may be driven by compressed air, or electricity but ahydraulic motor is preferred, that is, a motor driven by a liquid underpressure.

The employment of the servomechanism has the advantage that the camfollower needs only to support a very small load. Consequently no rolleris needed, and the follower can be sharp so as to follow the contour ofthe cam accurately.

The invention includes a process for winding yarn consisting ofsynthetic linear polyamides by means of a winding machine comprising incombination a spindle adapted to wind yarn packages, at traversemechanismtherefor, a rotary motor with crank to convey, by means ofconventional connecting means, a reciprocatory motion, correspondingapproximately to a simple harmonic motion, to said traverse mechanism,the rotary motor itself being moveably mounted so as to be capable ofreciprocating in the direction of the aforesaid reciprocatory motion, aservomechanism for causing the said rotary motor to reciprocate inaccordance with the contour of a cam, the follower of which actuates theservomechanism, so that the reciprocatory motion due to the rotary motoris superposed on the reciprocatory motion due to the cam, the contour ofwhich latter is designed so that the traverse mechanism produces adouble taper yarn package, wherein the rotary motor rotates at 50-100revolutions per minute. As already stated it is preferred that the saidrotary motor be hydraulic.

The shape or contour of the double taper packages obtained by thepresent winding machines is controlled, for a given setting of themachine (eg. length of traverse stroke, distance of reciprocation ofrotary motor) by the shape of the cam employed.

For the purpose of illustrating but not limiting the invention thefollowing embodiment thereof is described with reference to theaccompanying diagrammatic drawmgs.

In FIGURE 1 there is depicted in elevation a textile winding machinewhich is a downtwister, 1, is the spindle, 2 the double taper yarnpackage, 3 the ring rail attached to the reciprocating vertical rod 4,which constitute the traverse mechanism, 5 is the rotary motor, 6 thecrank conveying a reciprocatory motion to rod 4 by the connecting meanswhich comprise the reciprocating rod 7, the links 8, 9 and the bellcrank 10. The rotary motor is moveably mounted on the flanged wheels 11,which run on the track 12.

FIGURE 2 illustrates the downtwister in plan and is numbered similarly.In FIGURE 2 is also shown, on a somewhat larger scale for the sake ofclarity, the servoinechanism reversal valve 13, the cordate cam 14 andthe connecting links therefor 15, 16, 17, 13. 19 is the knife edge whichfollows the contour of the cam 14.

The mode of operation of the machine is as follows. The rotary motor isdriven hydraulically and serves to impart an approximately simpleharmonic reciprocatory motion to the rod 4, and thence to the ring rail3, by means of the rod 7 and the crank with the links 8 and 9. In thisconnection it is to be noted that the links 8 and 9 are of equal lengthand the arms of the crank 10 are also equal in length. Moreover ifperpendiculars be drawn from the pivot of the crank 11 to the rod 7 andto the rod 4 produced as shown by the dotted lines, then theseperpendiculars are equal in length. It may be added that it is notnecessary for the arms of crank 10 and the links 8 and 9 to berespectively equal, but if the links 8 and 9 are not equal then therespective arms of the crank 10 must be in the same ratio to each otheras are the links immediately connected to these arms. For example, ifthe link 9 is twice the length of the link 8, then the arm of the crank10 connected to the link 9 must be twice the length of the other arm ofcrank 10.

The rotary motor 5 itself is moved upon the rails 12 by means of aconventional hydraulic ram H which is controlled by the reversal valve13 so that, starting from the neutral position shown in the drawing inwhich the rams would be stationary, a small movement of the rod fromleft to right sets the ram in motion, so as to move the motor 5 alongits rails from right to left. Similarly, a small movement of the rod 20from right to left would cause the motor 5 to be moved from left toright. Now rod 20 is pivoted to the centre point of the link 16, whichin turn is connected via link 17 to link 13 which latter is fixedlypivoted to plate 21. At the centre of link 17 is mounted a knife edgewhich is urged resiliently (by a spring not shown) against the cam 14.The link 17 is twice the length of the link 15. Assuming for the moment,that the rotary motor 5 (although in rotation) is stationary upon itsrails 12, and that the reversal valve 13 is, as shown in FIGURE 2, inits neutral position. Now if the cam 14 revolve a little so that theknife edge follower 19 moves from left to right, the link 16 will bepushed to the right, pivoting at link 15, and pushing rod 20 from leftto right. But this latter motion of rod 20, as already explained above,will have the effect of moving the motor 5 along its rails from right toleft. This motion will push the upper end of link 16 (as drawn) fromright to left, and likewise move rod 20 from right to left until thereversal valve returns to its neutral position, when the motor 5 ceasesto move along its rails. Similarly, if the cam 14 push the knife edgefollower 19 from right to left, the motor 5 will be moved along itsrails from left to right until the reversal valve again returns to itsneutral position. In this way by means of the scrvomechanism comprisingthe reversal valve 13 and the ram the motor 5 is made to move along itsrails in accordance with the motion of the cam follower 19 as the cam 14revolves, because the valve 13 always tends to remain at its neutralposition. The point 22 where rods 16 and 20 are pivoted will accordinglyin practice not move. Since the pivot at 21 is a fixed point and link 13equal to the lower half (as drawn) of link 16, it can be deduced thatthe knife edge 19 will move along a nearly straight line (shown dotted)which is at right angles to the line (also shown dotted) which joins thepivots 21 and 22. It is remarked that the cam 14 is so disposed that thestraight line along which the knife edge 19 moves passes, when producedor extended, through the centre of the cam 23.

As an example of the operating conditions of the above downtwister thefollowing data are quoted:

Yarnpolyhexamethylene adipamide yarn of 20 filaments of 3 denier each;

Bobbin-l%" diameter tube;

Speed of spindle-7,500 revolutions per minute;

Rate of yarn wind-up--1,500 feet per minute;

Rate of rotary motorcycles per minute;

Traverse stroke-4;

Distance of reciprocation of rotary motor-4";

Rate of cam-4 5 minutes per revolution.

The shape or profile of the cam in the present embodiment of theinvention corresponds to the following polar coordinates which extendfrom 0180. Since the cam is symmetrical the radii from l80-360 areidentical but in the reverse order.

Angle of Cam Angle of Cam rotation radius in rotation radius in inchesinches What we claim is:

1. In a textile winding machine for winding a double taper yarn packagecomprising a spindle, means for rotating the spindle to wind yarn, ayarn guide for distributing yarn along the spindle and means forreciprocating the guide along the spindle in approximately simpleharmonic motion; the improvement in which said reciprocating meanscomprises a rotary motor, crank means connecting the motor to said yarnguide to reciprocate said guide when said motor turns, means mountingsaid motor for reciprocating motion, a cam, means for rotating said cam,follower means in operative relationship with said cam, and aservomechanism for reciprocating said motor in response to the movementof said follower, when said cam rotates.

2. Textile winding machine as claimed in claim 1, wherein the rotarymotor is a hydraulic motor.

References Cited in the file of this patent UNITED STATES PATENTSBergmann et al. Apr. 5, 1910 Abbott Jan. 4, 1944 Bauer Dec. 27, 1949Smith Nov. 13, 1951

